Fix test failure

cdcab26 removed excessive clearing of the windows. But it caused the
problem where the right side of the preview window border was not
cleared when hiding the preview window with the scrollbar disabled.

src/terminal.go

@@ -2113,9 +2113,9 @@ func (t *Terminal) printList() {
 
 func (t *Terminal) printBar(lineNum int, forceRedraw bool, barRange [2]int) bool {
 	hasBar := lineNum >= barRange[0] && lineNum < barRange[1]
-	if len(t.scrollbar) > 0 && (hasBar != t.prevLines[lineNum].hasBar || forceRedraw) {
+	if hasBar != t.prevLines[lineNum].hasBar || forceRedraw {
 		t.move(lineNum, t.window.Width()-1, true)
-		if hasBar {
+		if len(t.scrollbar) > 0 && hasBar {
 			t.window.CPrint(tui.ColScrollbar, t.scrollbar)
 		}
 	}